books.google.co.uk - Gem hunting can be like playing the geological lottery. You may spend hours performing backbreaking work and pay fees for access to mine tailings only to find a few semiprecious stones that aren't worth much. Another person may randomly reach into a pile of dirt and pull out a diamond worth thousands...https://books.google.co.uk/books/about/GEM_HUNTER.html?id=Az2_CQAAQBAJ&utm_source=gb-gplus-shareGEM HUNTER